Transitioning from recommendation to requirement: a systematic review of maternal immunization mandates, jurisdictional feasibility, and equity impacts

Abstract Maternal immunization is a key element in preventing perinatal disease, yet the shift from strong recommendation to mandatory policy remains controversial. In this systematic review, we provide the first comprehensive assessment of biomedical evidence, legal feasibility, ethical justification, and equity considerations related to maternal vaccination mandates. We analyzed randomized and observational studies, systematic reviews, clinical and legal guidelines, and qualitative analyses evaluating maternal vaccination against influenza, Tdap, COVID-19, and respiratory syncytial virus (RSV), and explicitly compared these interventions with infant nirsevimab to contextualize policy options. Thirty-six studies met the inclusion criteria. Maternal RSV vaccination reduced severe infant RSV infection by approximately 60%–80% within the first 6 months postpartum, with no safety concerns. Tdap and influenza vaccines showed strong protection and favorable safety profiles, while COVID-19 vaccine data—primarily observational—were reassuring. Despite these benefits, vaccine uptake remained suboptimal and unevenly distributed, highlighting ongoing disparities. Policy mapping revealed no pregnancy-specific mandates in Europe or the United States, and ethical analyses suggested that mandates would only be proportionate under conditions of high disease burden, proven safety, and failure of less-restrictive approaches. Modeling indicated that opt-out strategies and combined maternal–infant approaches might achieve greater and more equitable health gains compared to mandates. These findings offer policymakers and clinicians a comprehensive, multidisciplinary overview at a critical moment, aiding evidence-based decisions on maternal immunization policies.